Probability of severe weather within 25 miles of a point.Hatched Area: 10% or greater probability of significant severe within 25 miles of a point.

SPC AC 211730
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1130 AM CST SAT JAN 21 2012
VALID 221200Z - 231200Z
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE MID-SOUTH/LOWER AND
MIDDLE MS VALLEY TO OH/TN VALLEYS...
...SYNOPSIS...
A PROGRESSIVE LARGE SCALE PATTERN WILL PREVAIL THROUGH SUNDAY OVER
THE CONUS. AN UPPER TROUGH /AND ASSOCIATED STRONG MID-UPPER JET/ NOW
OVER THE CONUS WEST COAST WILL REACH THE PLAINS EARLY SUNDAY...AND
EVENTUALLY TAKE ON MORE OF A NEGATIVE TILT TOWARD THE MIDDLE/UPPER
MS RIVER VALLEY AND MIDWEST SUNDAY NIGHT. THIS SYSTEM WILL BE A
CONSIDERABLE FACTOR IN TERMS OF SEVERE CONVECTIVE POTENTIAL
ESPECIALLY SUNDAY NIGHT/EARLY MONDAY. FARTHER WEST...A SECONDARY
UPPER TROUGH/STRONG JET ALOFT WILL REACH THE WEST COAST BY EARLY
MONDAY.
...ARKLATEX/OZARKS AND MID-SOUTH TO MS/TN RIVER VALLEYS...
AN APPRECIABLE SEVERE EVENT IS POSSIBLE ACROSS THE REGION SUNDAY
NIGHT/EARLY MONDAY...INCLUDING THE POTENTIAL FOR TORNADOES AND
DAMAGING WINDS. AN UPGRADE TO A CATEGORICAL MODERATE RISK MAY BE
WARRANTED IN SUBSEQUENT OUTLOOKS FOR PORTIONS OF THE REGION.
GIVEN THE LARGE SCALE SCENARIO AS PREVIOUSLY DESCRIBED...AND THAT A
RELATIVELY MOISTURE-RICH AIRMASS WILL ONLY BE SUPPRESSED TO THE GULF
COAST REGION WITH THE DAY-1 FRONTAL PASSAGE...A RELATIVELY
QUICK/QUALITY RETURN OF BOUNDARY LAYER MOISTURE IS ANTICIPATED
ACROSS THE REGION ON SUNDAY AHEAD OF THE APPROACHING PLAINS UPPER
TROUGH. THIS RELATIVELY MOIST/BROAD WARM SECTOR WILL BE TO THE
EAST-SOUTHWARD OF THE PRIMARY SURFACE CYCLOGENESIS FROM THE
SOUTH-CENTRAL PLAINS TO THE LOWER MO VALLEY AND EVENTUALLY THE LAKE
MI VICINITY BY EARLY MONDAY. NEAR AN EASTWARD-ADVANCING DRY LINE AND
/MORE SO/ PACIFIC FRONT...INITIAL DEEP CONVECTIVE DEVELOPMENT MAY
OCCUR ACROSS PORTIONS OF THE ARKLATEX/MID-SOUTH AS EARLY AS LATE
AFTERNOON /OR MORE LIKELY/ SUNDAY EVENING. MORE DISCRETE/POTENTIALLY
SUPERCELLULAR DEVELOPMENT COULD ALSO OCCUR ACROSS THE WARM SECTOR
ACROSS THE LOWER MS VALLEY AS THE BOUNDARY LAYER CONTINUALLY
MOISTENS/CAPPING ALOFT ABATES.
GIVEN MORE THAN ADEQUATE MOISTURE/DESTABILIZATION...A ROBUST WIND
FIELD /HIGHLIGHTED BY 90-100 KT AROUND 500 MB AND 55-65 KT WITHIN
THE LOWEST 1-2 KM/ WILL FAVOR HIGHLY ORGANIZED STORM MODES WITH
ASSOCIATED SEVERE POTENTIAL SUNDAY NIGHT/EARLY EVENING...WITH AN
ISOLATED STRONG TORNADO/WIND DAMAGE EPISODE PLAUSIBLE. CURRENT
THINKING IS THAT A MULTI-FACETED STORM MODE SHOULD EVOLVE THROUGH
SUNDAY EARLY/MID-EVENING...INCLUDING INITIAL SEMI-DISCRETE
SUPERCELLS AHEAD OF WHAT WILL BE A TENDENCY FOR
QUICK-CLUSTERING/LINEAR EVOLUTION IN CLOSER PROXIMITY TO THE
ADVANCING PACIFIC COLD FRONT. A PREVALENT QUASI-LINEAR MODE/FAST
EAST-NORTHEASTWARD MOVING SQUALL LINE IS LIKELY BY LATE SUNDAY
NIGHT...ESPECIALLY FROM MS/AL INTO PORTIONS OF THE TN VALLEY/LOWER
OH VALLEY. AS SUCH...THE SEVERE THREAT /IN AN ISOLATED SENSE AT THE
VERY LEAST/ WILL LIKELY CONTINUE WELL THROUGH THE EARLY MORNING
HOURS OF MONDAY.
...OH VALLEY...
FARTHER NORTH...THE EXACT DEGREE OF LOW-LEVEL MOISTENING AND
DESTABILIZATION IS INHERENTLY MORE QUESTIONABLE...ESPECIALLY GIVEN
RECENT WINTER-TYPE PRECIPITATION ACROSS PORTIONS OF THE MIDWEST
WHICH PARTIALLY COINCIDES WITH THE EXPECTED SURFACE LOW TRACK/BRUNT
OF DPVA AS THE UPPER SYSTEM EVENTUALLY TAKES ON A MORE NEGATIVE
TILT. THAT SAID...A ROBUST WIND FIELD/LATE NIGHT DEEPENING PHASE OF
THE CYCLONE MAY CONTRIBUTE TO A RESPECTABLE THREAT FOR WIND
DAMAGE/PERHAPS A FEW TORNADOES EVEN WHERE NEAR-SURFACE INSTABILITY
IS SCANT ACROSS THE LOWER OH VALLEY.
..GUYER.. 01/21/2012
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NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 0700Z